Troubles when i add recourses to my library

Hello,
Every time I try to add new items or sources to my library in EN, and Back to work on WORD, it never stop ‘thinking’ like something is happening or stuck. Restarting and wait couple of minutes to see the syncing is done.
Too much time for nothing.and it stop responding. I use Mac pro, and EN 20
How to deal with that please?